Update:
I got the CFW Enabler 3.30 working on my PSP 3004 and am able to play ISOs on it now
This tutorial proved quite helpful -
http://kefler.110mb.com/index.html
Steps i used:
1. Install Original firmware 5.03 -
PSP Firmware 5.03 Download
2. Next installed the ChickHEN R2 Mod 2 (The Mod 2 is a big improvement, was able to load it with just 3-4 tries)
3. After loading the R2 i copied the CFW Enabler 3.30 onto my PSP and flashed it
Everything working great and took me all of 5 mins to do after i had all the files ready
Now been playing some really nice games like PataPon and WWE vs SD 2009